The invention relates to a fiberoptic filling level determination apparatus for liquid transparent media disposed in containers, with a light wave conductor that is at least partially immersible in the medium and is connected to a light source disposed externally of the container, whereby the difference in intensity between introduced light and exiting light is used to determine the filling level of the medium in the container.
A filling level determination apparatus of the aforementioned type is described in DE 32 35 591 C2; the known filling level determination apparatus comprises a light wave conductor that can be immersed in the container and that at its end that is immersible in the medium is ground at an angle or conically, and is polished. The light introduced into the light wave conductor via a light source is completely reflected at the appropriately split tip of the light wave conductor until the tip of the light wave conductor is submerged into the medium so that light then exits at the tip of the light wave conductor into the medium. By determining the difference in intensity between the introduced and the reflected light it is accordingly determined whether or not the tip of the light wave conductor has been submerged into the medium.
The known filling level determination apparatus has the drawback that respectively only one filling level can be determined that is dictated by the respective position of the tip of the light wave conductor in the container; therefore, it is furthermore proposed in DE 32 35 591 C2 to integrate into the described apparatus a further section of a light wave conductor having a tip that is correspondingly disposed in a different position, so that at least a second filling level can be detected. Further filling heights are respectively possible only by means of a multiplicity of corresponding light wave conductor arrangements. Thus, with the known filling level determination apparatus it is not possible to have a continuous filling level determination over the entire height of the container.
It is therefore an object of the present invention to provide a filling level determination apparatus that is based on the principle of fiberoptic filling level determination, and that enables a continuous determination of a filling level value.